title: Screening of MYH7, MYBPC3, and TNNT2 genes in Brazilian patients with hypertrophic cardiomyopathy.
abstract: BACKGROUND
  Hypertrophic cardiomyopathy (HC) is the most prevalent genetic cardiac disease caused by a mutation in sarcomeres, Z-disks, or calcium-handling genes and is characterized by unexplained left ventricular hypertrophy. The aim of this study was to determine the genetic profile of Brazilian patients with HC and correlate the genotype with the phenotype.
  
  
  METHODS
  We included 268 index patients from São Paulo city and 3 other cities in Brazil and extracted their DNA from whole blood. We amplified the coding sequencing of MYH7, MYBPC3, and TNNT2 genes and sequenced them with an automatic sequencer.
  
  
  RESULTS
  We identified causal mutations in 131 patients (48.8%). Seventy-eight (59.5%) were in the MYH7 gene, 50 (38.2%) in the MYBPC3 gene, and 3 (2.3%) in the TNNT2 gene. We identified 69 mutations, 24 not previously described. Patients with an identified mutation were younger at diagnosis and at current age, had a higher mean heart rate and higher nonsustained ventricular tachycardia frequency compared with those without a mutation. Patients with MYH7 gene mutations had a larger left atrium and higher frequency of atrial fibrillation than did patients with MYBPC3 gene mutations.
  
  
  CONCLUSIONS
  The presence of a mutation in one of the genes suggests a worse prognosis. Mutations in the MYH7 gene, rather than in the MYBPC3 gene, were also related to a worse prognosis. This is the first work characterizing HC molecular epidemiology in the Brazilian population for the 3 most important genes.
authors.affiliation: Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor), University of São Paulo, São Paulo, Brazil. Electronic address: julia.marsiglia@usp.br.
authors.forename: Julia Daher Carneiro
authors.initials: JD
authors.lastname: Marsiglia
authors.forename: Flávia Laghi
authors.initials: FL
authors.lastname: Credidio
authors.forename: Théo Gremen Mimary
authors.initials: TG
authors.lastname: de Oliveira
authors.forename: Rafael Ferreira
authors.initials: RF
authors.lastname: Reis
authors.forename: Murillo de Oliveira
authors.initials: Mde O
authors.lastname: Antunes
authors.forename: Aloir Queiroz
authors.initials: AQ
authors.lastname: de Araujo
authors.forename: Rodrigo Pinto
authors.initials: RP
authors.lastname: Pedrosa
authors.forename: João Marcos Bemfica
authors.initials: JM
authors.lastname: Barbosa-Ferreira
authors.forename: Charles
authors.initials: C
authors.lastname: Mady
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Krieger
authors.forename: Edmundo
authors.initials: E
authors.lastname: Arteaga-Fernandez
authors.forename: Alexandre da Costa
authors.initials: Ada C
authors.lastname: Pereira
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D024722:Cardiac Myosins / Q000235:genetics* / Q000378:metabolism; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D004247:DNA / Q000235:genetics*; D005260:Female; D005820:Genetic Testing / Q000379:methods*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics* / Q000378:metabolism; D009218:Myosins; D010641:Phenotype; D016133:Polymerase Chain Reaction; D015995:Prevalence; D020107:Troponin T / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult; D000099163:Myosin Binding Protein C
chemical_list: D024722:Cardiac Myosins; D002352:Carrier Proteins; D004247:DNA; D018995:Myosin Heavy Chains; D009218:Myosins; D020107:Troponin T; D000099163:Myosin Binding Protein C; C501641:MYH7 protein, human; C545568:TNNT2 protein, human